This invention relates, in general, to electronics and, more particularly, to physical sensor components.
Physical sensor components such as silicon pressure sensors can be used in automotive, industrial, consumer white goods, and various other applications. To provide compatibility with different chemical environments, encapsulants have been used to protect the silicon pressure sensor. However, none of these encapsulants are entirely impermeable to corrosive solutions. Furthermore, the encapsulants do not completely satisfy the customers"" stringent reliability requirements, and the encapsulants also do not enable the silicon pressure sensors to remain fully operative during their expected lifetimes. A common failure mechanism for a silicon pressure sensor having a prior art encapsulant involves diffusion of the corrosive media followed by the delamination of the encapsulant from the silicon pressure sensor. This delamination exposes portions of the sensor that subsequently corrode from the direct exposure to the chemical environments. In addition to this common failure mechanism, most of the encapsulants produce adverse mechanical effects on the performance of the silicon pressure sensor, and these adverse mechanical effects severely limit the use of the sensor.
Accordingly, a need exists for an improved physical sensor component that provides effective corrosion protection while not introducing adverse mechanical effects on the performance of the component.